* {
  margin: 0;
  padding: 0;
}

body {
  background-color: #e4dccc;
}

.display-b {
  display: block;
}

.display-n {
  display: none;
}

.bgc {
  position: absolute;
  top: 0;
  left: 0;
  z-index: -1;
  width: 100%;
  height: 100%;
}

.page-logo {
  display: block;
  position: relative;
  z-index: 2;
  width: 52.8vw;
  margin: 18vw auto 0;
}

.ip6 .page4 .page-logo,
.ip6 .page6 .page-logo {
  display: block;
  position: relative;
  z-index: 2;
  width: 52.8vw;
  margin: 16vw auto 0;
}

/* 向上箭头 */
/* 箭头 */
.arrow-up {
  position: absolute;
  bottom: 4.5vw;
  left: 45vw;
  z-index: 3;
  display: block;
  width: 10vw;
  animation: arrow_as 2s ease-in-out infinite;
}
@keyframes arrow_as {
  0%{transform:translate3d(0,0,0);}
  50%{transform:translate3d(0,-4vw,0);}
  100%{transform:translate3d(0,0,0);}
}